Given that a is the integral part of √ 13 and B is the fractional part of √ 13, find the value of A-B?

Given that a is the integral part of √ 13 and B is the fractional part of √ 13, find the value of A-B?

solution
√ 13 is between 3 and 4
A is the integral part of √ 13, B is the decimal part of √ 13
Then a = 3, B = √ 13-3
So A-B = 3 - (√ 13-3)
A-B = 6 - √ 13